Note:
Shipping weights are for the product only. Actual weight of shipment will be
different.

Hose
Connections

All
Classic Style DESCO Helmets are fitted to accept 1/2" Navy air hose with a 1
1/16" -17 Submarine Thread. Adapters are available to other fitting
configurations. The air inlet elbow and non-return valves are male threads to
the female hose end.

The
DESCO Air Hat and Browne Masks accept 5/16" or 3/8" air hose with a 9/16-18
Oxygen Thread. This fitting is a standard CGA welding fitting.

Air
Requirements

Helmets

DESCO
uses the air flow requirements as set forth in the U.S. Navy Diving Manuals for
the Mark V Helmet as a benchmark. Any DESCO Classic Style Helmet or the Air Hat
has an absolute minimum necessary airflow rate of 6 cfm at rest to properly
ventilate the helmet. As activity increases the airflow rate must be increased
to offset buildup of Carbon Dioxide in the helmet. For the Air Hat a minimum
working flow rate of 10cfm is recommended. Overbottom pressure is 100psi
constant.

Masks

The Browne
Mask was developed for the US Navy during World War Two. They have the most
extensive and complete working knowledge of the performance of these masks.
DESCO defers to them on the air requirements for the Browne Masks.

Excerpted
from the 1985 USN Diving Manual:

Flow
requirements 6.4.3.1 The Jack Browne mask requires constant gas flow to
prevent excessive accumulation of metabolically produced carbon dioxide. When
planning a diving operation ensure the primary air supply system is capable of
providing an average sustained flow of 4.5acfm for each diver including the
standby diver. In addition, for short durations of heavy work, the air supply
system must be capable of providing each diver in the water with a flow of
6acfm.

Pressure requirements
6.4.3.2
When using the Jack Browne mask, an overbottom pressure of 50psi must be
maintained.

Microphone/Speaker is held in place with 3M® VHB
Double Sided Foam tape.

Inside Air Elbow and
pigtail bulkhead fitting is
epoxied in place with 10 minute two part epoxy.

Neck
ring gasket is glued in place with sanding disk adhesive.

Approximate shipping weight is 34lbs.

The
Air Hat can be used with the provided neck dam or with drysuits fitted with a
DESCO type yoke.

The
complete DESCO Air Hat Manual is available for download on the
Downloads Page.

DESCO
Air Hat Welding Shield

Lens
dimensions 4 ½" x 5 ¼"

Screws
#10-32 x 7/8" Stainless Steel

U.S.
Navy Diving Helmets

The
DESCO Mark V and Helium Helmets are made to U.S. Navy specifications as
prescribed in the Bureau of Ships drawings.

Helmets listed below all use the Navy Mark V style dress collar.

U.S.
Navy Mark V Diving Helmet

Threading Specifications;

Air Inlet Elbow threading is 1 1/16" - 17 (Submarine Thread).

Communications elbow threading is 1.715 - 11.

Front Door Toggle Bolt threading is 1/2" - 13 NC.

Window Guard Screws are #8 - 32 NC.

Breastplate Stud threading is 1/2" - 12 NS.

Neck Ring Threads (interrupted) 9 13/64" - 6 NS

Head opening in Neck Ring 8 9/16"

Approximate shipping weight is 68lbs

U.S.
Navy Helium Helmet

Threading Specifications;

The common parts
between the Mark V Helmet and the Helium Helmet are identical (see Mark V specs).

High
Pressure Nozzle threading : 3/4"-16

Discharge Nozzle threading: 3/4"-16

Canister Elbow threading: 2 3/4"-8

Approximate shipping weight is 93lbs with canister.

Communications is via a standard Navy Mark V type plug.

DESCO Commercial Diving Helmets

The DESCO Commercial helmets all use a common
breastplate and bonnet platform. This breastplate style was used by multiple
manufacturers. Some DESCO Commercial Helmets were produced using the Mark V
bonnet shell in lieu of the standard "bubble" shell.

Models vary by window configuration, exhaust
type, and optional features. Refer to the helmet pages for detailed information
on each model's features.